And earlier this week he returned to the small village where he grew up to share his experience with local young people.

Speaking to BBC Scotland before the event at local museum and art gallery Timespan, he said he took the book with him on February's test flight.

"On the cover it has a picture of a Mercury capsule showing an astronaut inside," he said.

"This book really was an inspiration for me."

Mackay took a book about space flight that he was given when he was boy with him on February's test flight

Children turning up for Mackay's talk in Helmsdale

He said growing up in Helmsdale also inspired his dreams of becoming a pilot and going into space.

"It all began here," he said.

"The family's home was in the centre of Helmsdale and the village is at the natural entry point for low flying military aircraft moving to, and operating in, the middle of Sutherland.

"It was Buccaneers at that time from Royal Naval Air Station Lossiemouth (today RAF Lossiemouth) across the Moray Firth.

"They entered that area over Helmsdale at very high speed and very low level. And that looked incredibly exciting to me as a young boy.

"I would look up and think 'wow, I would like to do that'."

Mackay flew his test flight in February

Growing up in the Highlands not only exposed the young Mackay to the wonders of flight, it also made him curious about life outside the region.

Mackay says: "In a way the north Highlands is fairly remote and there was always part of me that wondered what it was like in other parts of the world.

"I had a hunger to go and see other places and other things. Growing up, I was also exposed to the Nasa Apollo missions."

Mackay flew at three times the speed of sound during February's flight

He added: "At certain points in my life people have called me a dreamer.

"And I would say to young children that dreams are good. It is better to have an impossible dream than no dream at all.

"If you have a dream and you really, really want it you have to work at it.

"By preparing yourself by getting the qualifications you need and then if you are lucky and in the right place and right time, you can grasp that opportunity."

Mackay's preparations to grasp his dream included first learning to fly while studying aeronautical engineering at the University of Glasgow in 1977.

He joined the RAF and his 16 years as a military pilot included commanding fast jet test flights in the 1990s. After the RAF, he flew Boeing 747 and Airbus 340 passenger aircraft, before joining Sir Richard Branson's Virgin Galactic, and the commercial space race.

Mackay is Virgin Galactic's chief pilot, and February's test flight marked a crucial step in the company's ambition to offer flights into space.

Mackay's early experiences of travelling at speed was sledging down a hill he now describes as "frighteningly steep"

The test flight saw Mackay travel at three times the speed of sound.

Standing on a hill overlooking Helmsdale, Mackay recalls one of his early experiences of travelling at speed with his family and friends.

"When I look down there it seems crazy to think that in winter, in the snow, we used to sledge down there," he says.

"It is frighteningly steep when I look at it now.

"We used to build up a heck of a speed and just jump off before we hit the stone dyke at the end.